Switch to output parse of `--version` to determine ls version

[ghthor]

Alternative to #317 to fix #312.

I don't have a mac to test this on, if someone with a mac could test and confirm this is working as expected that would be excellent.

@patbl

$ if ! ls --version | grep GNU >/dev/null 2>&1; then echo "BSD"; else echo "GNU"; fi
GNU
Thu Jun 23 08:29:15 AM EDT 2022
0 ghthor@hivemind ~/.scm_breeze [test-bsd-ls]

[jeffbyrnes]

On macOS 12.4 Monterey, there is no --version flag:

Jeffs-iMac:~ jeffbyrnes$ ls --version | grep GNU
ls: unrecognized option `--version'
usage: ls [-@ABCFGHILOPRSTUWabcdefghiklmnopqrstuvwxy1%,] [--color=when] [-D format] [file ...]

So it would seem this won’t work.

[ghthor]

On macOS 12.4 Monterey, there is no --version flag:

OO, we can probably work with this.

Let's try

if ! (ls --version 2>/dev/null || echo "BSD") | grep GNU >/dev/null 2>&1; then echo "BSD"; else echo "GNU"; fi

[jeffbyrnes]

I get

🕙 11:22:55 jeffbyrnes in ~
♠ if ! (ls --version 2>/dev/null || echo "BSD") | grep GNU >/dev/null 2>&1; then echo "BSD"; else echo "GNU"; fi
BSD

[ghthor]

I get

🕙 11:22:55 jeffbyrnes in ~
♠ if ! (ls --version 2>/dev/null || echo "BSD") | grep GNU >/dev/null 2>&1; then echo "BSD"; else echo "GNU"; fi
BSD

:thumbsup: